Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh vai » hanh vi, hanh va, hanh tai
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, dua tren
sac ky » sai ky
cac lo » cac lop, cac co, cac bo
lo va » lo van, lao va, ly va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: thu ((cac ky) or (sac ky)) nang xa hoi. hieu va cac lo va hanh vai ((cua tre) OR (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu ((cac ky) OR (sac ky)) nang xa hoi. hieu va cac lo va hanh vai ((cua tre) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu ((cac ky) or (sac ky)) nang xa hoi. hieu va cac lo va hanh vai ((cua tre) OR (cua triet))".
• Adding a wildcard symbol may retrieve word variants: thu ((cac ky) or (sac ky)) nang xa hoi. hieu va cac lo va hanh vai ((cua tre) OR (cua triet))*.